Surgical stapling instruments including a cartridge having multiple staple sizes

ABSTRACT

A surgical stapling apparatus includes a staple cartridge and an anvil member. The staple cartridge includes a plurality of surgical fasteners disposed in rows of retention slots. The staple cartridge may have an annular or linear configuration of retention slots. The tissue contacting surface of the staple cartridge may be tapered or stepped. The anvil member has a tissue contacting surface that includes a number of pockets arranged for substantially aligning with the retention slots. In addition, the tissue contacting surface of the anvil member may complement the tissue contacting surface of the staple cartridge.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No. 12/245,135now patented U.S. Pat. No. 8,123,100 filed Oct. 3, 2008, which is adivisional of U.S. application Ser. No. 11/974,571 filed Oct. 15, 2007,now patented U.S. Pat. No. 7,481,349, which is a divisional applicationof No. 11/204,060 filed Aug. 15, 2005, now patented U.S. Pat. No.7,407,075, and the disclosures of each of the above-identifiedapplications are hereby incorporated by reference in their entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to surgical stapling instruments and,more particularly, to surgical stapling instruments including acartridge having multiple staple sizes.

2. Background of Related Art

There are several known types of surgical stapling instrumentsspecifically adapted for use in various procedures such as end-to-endanastomosis, gastrointestinal anastomosis, endoscopic gastrointestinalanastomosis, and transverse anastomosis. Examples of staplinginstruments for these various procedures can be found in U.S. Pat. Nos.5,915,616; 6,202,914; 5,865,361; and 5,964,394.

Each surgical stapling instrument includes an anvil which isapproximated relative to a staple cartridge. The staple cartridgetypically has one or more laterally spaced rows of staples which,depending on the particular stapling instrument, may be arranged in alinear or non-linear configuration. The anvil includes staple formingdepressions which are aligned with and/or in registration with thestaple slots of the staples in the cartridge. In use, each of thesurgical stapling instruments involves the gripping of tissue to befastened, the ejecting of individual staples, the forcing of staplesthrough the gripped tissue and the closing and/or forming of the staplesagainst the staple forming depressions of the anvil.

A common issue in transecting tissue and/or in anastomosis procedures,employing any one of the surgical stapling instruments disclosed above,is the balance between anastomotic strength and the degree of hemostasisachievable. It is known to include different size staples in a surgicalstapling apparatus having a constant gap (i.e. a uniform distance)between an anvil and a staple cartridge.

SUMMARY

The present disclosure is directed towards surgical stapling instrumentsconfigured to effectuate an improved balance between the anastomoticstrength and the degree of hemostasis at the tissue interface. Inparticular, embodiments of the present disclosure include surgicalfasteners of different sizes. Further still, the distance between ananvil member and a staple cartridge (i.e. the gap) varies from acenterline of the staple cartridge to an outer edge of the staplecartridge. Combining the different sizes of surgical fasteners with thevarying gap between the anvil member and the staple cartridge improvesthe anastomotic strength and the degree of hemostasis at the tissueinterface.

According to one aspect of the disclosure, the surgical staplinginstrument includes a first structure defining having an anvil memberoperatively associated therewith, and a second structure defining astaple cartridge operatively associated therewith. The staple cartridgehas a tissue contacting surface with a stepped cross-sectional profile.The tissue contacting surface of the staple cartridge also includes aplurality of retention slots formed therein for retaining a surgicalfastener. During operation of the surgical stapling instrument, theanvil member and the staple cartridge can be approximated relative toone another.

The stepped tissue contact surface of the staple cartridge defines aplurality of tissue contacting surfaces each having a different height.In one embodiment, the stepped tissue contacting surface of thecartridge includes an inner tissue contacting surface having a height,an intermediate tissue contacting surface having a height less than theheight of the inner tissue contacting surface, and an outer tissuecontacting surface having a height less than the height of theintermediate tissue contacting surface.

The inner, intermediate, and outer tissue contacting surfaces eachinclude at least one row of retention slots formed therein. A pluralityof surgical fasteners is disposed, one each, in each retention slot.Each surgical fastener includes a backspan and a pair of descendinglegs.

The surgical fasteners retained in the retention slots formed in theinner tissue contacting surface have a first leg length, the surgicalfasteners retained in the retention slots formed in the intermediatetissue contacting surface have a second leg length, and the surgicalfasteners retained in the retention slots formed in the outer tissuecontacting surface have a third leg length. In one embodiment, thesurgical fasteners retained in the retention slots formed in the innertissue contacting surface have a leg length of about 2.3 mm, while thesurgical fasteners retained in the retention slots formed in theintermediate tissue contacting surface have a leg length of about 3.5mm, and the surgical fasteners retained in the retention slots formed inthe outer tissue contacting surface have a leg length of about 4.1 mm.

It is envisioned that the surgical stapling instrument can be acircular-type surgical stapling instrument wherein the anvil member andthe staple cartridge can be annular. In one embodiment, the plurality oftissue contacting surfaces decreases in height in a radially outwarddirection. Accordingly, the inner tissue contacting surface is closestto the center and the outer tissue contacting surface is furthest fromthe center of the annular staple cartridge. Moreover, surgical fastenershaving relatively short leg lengths are retained in the retention slotsclosest to the center of the annular staple cartridge while surgicalfasteners having relatively longer leg lengths are retained in theretention slots furthest from the center of the annular staplecartridge.

It is further envisioned that the surgical stapling instrument can be alinear-type surgical stapling instrument wherein the anvil member andthe staple cartridge are linear. In these instruments, the staplecartridge and/or the anvil member may define a knife cut line.Accordingly, the plurality of tissue contacting surfaces decreases inheight in a direction orthogonally outward from the knife cut line. Inparticular, the inner tissue contacting surface is closest to the knifecut line while the outer tissue contacting surface is furthest from theknife cut line. In addition, surgical fasteners having relatively shortleg lengths are retained in the retention slots closest to the knife cutline while surgical fasteners having relatively longer leg lengths areretained in the retention slots furthest from the knife cut line.

It is envisioned that the anvil member can have a tissue contactingsurface with a stepped cross-sectional profile including a plurality oftissue contacting surfaces, wherein each tissue contacting surface has adifferent height. In addition, each one of the plurality of tissuecontacting surfaces can include at least one annular and/or linear rowof surgical fastener forming depressions formed therein.

In one embodiment, the anvil member can have a tissue contacting surfacewhich is shaped (i.e. stepped) to complement the stepped tissuecontacting surface of the staple cartridge. In another embodiment, theanvil member can have a tissue contacting surface which is stepped whilethe tissue contacting surface of the staple cartridge is substantiallyplanar. In yet another embodiment, the anvil member can have a tissuecontacting surface which is shaped to substantially complement thestepped tissue contacting surface of the staple cartridge (i.e. thedepths of the tissue contacting surfaces of the stepped anvil member arenot equal to the heights of the individual tissue contacting surfaces ofthe tissue contacting surface of the staple cartridge). In still anotherembodiment, the anvil member can have a tissue contacting surface whichis stepped to minor the tissue contacting surface of the staplecartridge (i.e. the depths of individual tissue contacting surfaces ofthe tissue contacting surface of the anvil member are substantiallyequal to the depths of the individual tissue contacting surfaces of thestaple cartridge).

In other embodiments of the present disclosure, a surgical staplinginstrument includes an operative tool disposed at one end thereof. Theoperative tool includes an anvil member and a staple cartridge. Thestaple cartridge may be included in a disposable surgical staplingapparatus or in a reusable surgical stapling apparatus. Further still, areplaceable loading unit may be located in either the disposable or thereusable surgical stapling apparatus. In one embodiment, the replaceableloading unit includes a staple cartridge, while an alternate embodimentof the replaceable loading unit includes a staple cartridge and an anvilmember. In particular, the staple cartridge includes a plurality ofsurgical fasteners disposed in rows of retention slots. The surgicalfasteners may have different leg lengths wherein a plurality of surgicalfasteners having substantially the same leg length is disposed in a row.A number of fastener ejection members are disposed in the staplecartridge wherein each fastener ejection member includes a plurality ofstaple pushers for ejecting the surgical fasteners in cooperation withan actuation mechanism.

The staple cartridge may include an angled tissue contacting surfacethat peaks at a centerline of the staple cartridge and tapers towardsouter walls of the staple cartridge. Alternatively, the tissuecontacting surface of the staple cartridge may have a surface that isparallel with the bottom surface of the staple cartridge or parallel toa plane defined by the backspans of surgical fasteners disposed in aselected row. The parallel surface of the tissue contacting surface hasa width dimension that is sufficient to accommodate at least one row ofsurgical fasteners. The staple cartridge may include a knife channel.

In cooperation with the presently disclosed staple cartridge, the anvilmember may include a planar tissue contacting surface that issubstantially parallel to the bottom surface of the staple cartridge orparallel to a plane defined by the backspans of surgical fastenersdisposed in a selected row. In the alternative, the tissue contactingsurface of the anvil member may be angled in an opposed manner to theangle of the tissue contacting surface of the staple cartridge. Furtherstill, the tissue contacting surface of the anvil member may have aplanar surface that is substantially parallel to the bottom surface ofthe staple cartridge or parallel to a plane defined by the backspans ofsurgical fasteners disposed in a selected row and tapered surfaces thatdefine angles opposite to the angles defined by the tissue contactingsurface of the staple cartridge. The parallel surfaces of the anvilmember have a width dimension that corresponds to a width dimension ofthe parallel surface of the staple cartridge.

It is further contemplated that one embodiment of the surgical staplingapparatus includes structures for supplemental sealing of the fastenedlayers of tissue. In one embodiment, the surgical stapling apparatusincludes a wound closure assembly having a reservoir and a supply line.The reservoir is adapted for storing a quantity of a wound closurematerial and is fluidly coupled to the staple cartridge via the supplyline for delivering amounts of the wound closure material to theplurality of retention slots.

The presently disclosed surgical stapling instruments, together withattendant advantages, will be more clearly illustrated below by thedescription of the drawings and the detailed description of theembodiments.

Other objects and features of the present disclosure will becomeapparent from consideration of the following description taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the presently disclosed surgical stapling apparatus aredescribed herein with reference to the accompanying drawings, wherein:

FIG. 1 is a perspective view of a surgical stapling instrumentconstructed in accordance with the present disclosure;

FIG. 2 is a schematic cross-sectional side elevational view of thedistal end portion of the surgical stapling instrument of FIG. 1, astaken through 2-2 of FIG. 1;

FIG. 3A is an enlarged schematic representation of the indicated area ofFIG. 2, illustrating tissue contacting surfaces in accordance with analternate embodiment of the present disclosure;

FIG. 3B is an enlarged schematic representation of the indicated area ofFIG. 2, illustrating tissue contacting surfaces in accordance withanother embodiment of the present disclosure;

FIG. 3C is an enlarged schematic representation of the indicated area ofFIG. 2, illustrating tissue contacting surfaces in accordance with stillanother embodiment of the present disclosure;

FIG. 3D is an enlarged schematic representation of the indicated area ofFIG. 2, illustrating tissue contacting surfaces in accordance with afurther embodiment of the present disclosure;

FIG. 4 is a perspective view of an alternative surgical staplinginstrument constructed in accordance with the present disclosure;

FIG. 5 is a perspective view of yet another surgical stapling instrumentconstructed in accordance with the present disclosure;

FIG. 6 is a perspective view of still another surgical staplinginstrument constructed in accordance with the present disclosure;

FIG. 6A is a perspective view of a portion of an anvil member of FIG. 6;

FIG. 7 is a schematic cross-sectional side elevational view of thedistal end portion of the surgical stapling instruments of FIGS. 4-6, astaken through 7-7 of each of FIGS. 4-6;

FIG. 7A is a schematic cross-sectional side elevational view of analternate embodiment of the distal portion of the surgical staplinginstrument of FIG. 6

FIG. 8 is a perspective view of a staple cartridge according to anotherembodiment of the present disclosure;

FIG. 9 is a cross-sectional end view of the staple cartridge of FIG. 8showing a first arrangement of surgical fasteners;

FIG. 10 is an alternate embodiment of the staple cartridge of FIG. 9illustrating a second embodiment of the surgical fasteners;

FIG. 11 is an alternate embodiment of an anvil member and the staplecartridge of FIG. 10;

FIG. 12 is a further embodiment of the staple cartridge of FIG. 8;

FIG. 13 is another embodiment of the anvil member and the staplecartridge of FIG. 12;

FIG. 14 is another embodiment of the staple cartridge and anvil memberof FIG. 8;

FIG. 15 is alternate embodiment of an anvil member with the staplecartridge of FIG. 14; and

FIG. 16 is a cross-sectional side elevational view of the resultingtissue interface following the firing of surgical stapling instrument ofFIGS. 7 and 10-15.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the presently disclosed surgical stapling instrumentswill now be described in detail with reference to the drawing figureswherein like reference numerals identify similar or identical elements.In the drawings and in the description which follows, the term“proximal”, as is traditional, will refer to the end of the surgicalstapling instrument which is closest to the operator while the term“distal” will refer to the end of the device which is furthest from theoperator.

The present disclosure relates to a staple cartridge and an anvil memberfor use in a disposable or re-usable surgical stapling apparatus. Thepresently disclosed staple cartridge and anvil member, as will bediscussed in detail hereinbelow, may be used with any of the surgicalstapling apparatus shown in FIG. 1, 4, 5, or 6. In addition, areplaceable loading unit may be located in either the disposable or thereusable surgical stapling apparatus. In one embodiment, the replaceableloading unit includes a staple cartridge, including any of the staplecartridges disclosed herein. Alternatively, the replaceable loading unitincludes the staple cartridge and an anvil member, including any of theanvil members disclosed herein. In combination with the disposable orthe reusable surgical stapling apparatus, the replaceable loading unitprovides improved flexibility of the respective surgical staplingapparatus in that the respective surgical stapling apparatus is readilyadaptable for different stapling procedures.

Referring now in detail to FIGS. 1-2, in which like reference numeralsidentify similar or identical elements, a surgical stapling instrument,in accordance with a first embodiment of the disclosure, is generallydesignated as 100.

As seen in FIG. 1, surgical stapling instrument 100 includes a handleassembly 102 having at least one pivotable actuating handle member 103,and further includes advancing means 105. Extending from handle assembly102, there is provided a tubular body portion 104 which may beconstructed so as to have a curved shape along its length. Tubular bodyportion 104 terminates in a fastener ejection member assembly 106 havinga circular staple cartridge 118 including a tissue contacting surface121 disposed at a distal end thereof.

As seen in FIG. 2, tissue contacting surface 121 is stepped including anouter tissue contacting surface 121 a, an intermediate tissue contactingsurface 121 b, and an inner tissue contacting surface 121 c. Each tissuecontacting surface 121 a-121 c has a different height from one anotheras measured from a bottom surface 131 of a staple pusher or fastenerejection member 130. Specifically, tissue contacting surfaces 121 a-121c are planar structures that are substantially parallel to one another,but are not co-planar (i.e. stepped) with one another. In addition, eachtissue contacting surface 121 a-c defines a planar axis that extendsthrough the respective tissue contacting surface 121 a-c. A first wallsurface interconnects tissue contacting surfaces 121 a and 121 b, whilea second wall surface interconnects tissue contacting surfaces 121 b and121 c. The first and second wall surfaces are planar structures whereineach wall surface defines a planar axis. In one embodiment, the planaraxes of the wall surfaces are orthogonal to the planar axes of tissuecontacting surfaces 121 a-c.

Inner tissue contacting surface 121 c has the greatest height, outertissue contacting surface 121 a has the least height, and intermediatetissue contacting surface 121 b has a height between the heights ofouter and inner tissue contacting surfaces 121 a, 121 c. While tissuecontacting surfaces 121 a-121 c are shown as increasing in height fromouter tissue contacting surface 121 a to inner tissue contacting surface121 c (i.e. radially inward), it is within the scope of the presentdisclosure that the heights of each tissue contacting surface can varydepending on the particular surgical procedure. For example, tissuecontacting surfaces 121 a-121 c can increase in height in a radiallyoutward direction, the intermediate tissue contacting surface 121 b canbe the highest or the lowest tissue contacting surface, or at least twoof tissue contacting surfaces 121 a-121 c can have the same height.

In one embodiment, each tissue contacting surface 121 a-121 c includes arespective annular row 119 a-119 c of retention slots 123 formedtherein. Each retention slot 123 of annular rows 119 a-119 c isconfigured and dimensioned to retain a staple or surgical fastener 125therein. Each surgical fastener 125 includes a backspan (not shown) anda pair of depending legs 25. In one embodiment, each annular row 119a-119 c of slots 123 includes a respective surgical fastener 125 a-125 chaving its own characteristic features.

As seen in FIG. 2, legs 25 a of surgical fasteners 125 a have a firstleg length, legs 25 b of surgical fasteners 125 b have a second leglength, and legs 25 c of surgical fasteners 125 c have a third leglength. In particular, surgical fasteners 125 a-125 c increase in heightin a radially outward direction. In one embodiment, legs 25 c ofsurgical fasteners 125 c have a leg length of about 2.3 mm, legs 25 b ofsurgical fasteners 125 b have a leg length of about 3.5 mm, and legs 25a of surgical fasteners 125 a have a leg length of about 4.1 mm. Assuch, inner tissue contacting surface 121 c has the greatest height andretains surgical fasteners 125 c having the shortest leg lengths, andouter tissue contacting surface 121 a has the least height and retainssurgical fasteners 125 a having the longest leg lengths. Having tissuecontacting surface 121 step progressively downward at intermediatetissue contacting surface 121 b and then again at outer tissuecontacting surface 121 a results in the formation of surgical fasteners125 b and 125 c, respectively. It is envisioned and within the scope ofthe present disclosure that any number of arrangements are possible.

While a single annular row 119 a-119 c of retention slots 123 is shownfor each tissue contacting surface 121 a-121 c, it is envisioned andwithin the scope of the present disclosure that each tissue contactingsurface 121 a-121 c can include multiple annular rows of retentionslots.

As seen in FIG. 2, a fastener ejection assembly 106 of surgical staplinginstrument 100 includes fastener ejection member 130 disposed withinstaple cartridge 118. Fastener ejection member 130 includes a proximalportion 132 having a generally frusto-conical shape and a distal portiondefining concentric rings of peripherally spaced staple pushers 134 a-c,each one of which is received within a respective staple retention slot123 and is cooperative with its respective surgical fastener 125 a-cdisposed in annular rows 119 a-c. In one embodiment, it is envisionedthat proximal portion 132 of fastener ejection member 130 is configuredand dimensioned to be contacted by a distal end of a driver tube 138.Hence, upon advancing fastener ejection member 130 by advancing drivertube 138, staple pushers 134 a-c will pass further into retention slots123 thereby pushing surgical fasteners 125 contained therein axiallyoutward.

In an alternate embodiment, staple pushers 134 a-c of fastener ejectionmember 130 have different heights for cooperating with different sizedsurgical fasteners. In particular, staple pushers 134 a-c are sized suchthat when surgical fasteners 125 a-c are disposed in their respectiveannular rows 119 a-c, tips of surgical fasteners 125 a-c are locatedsubstantially in the same plane despite the difference in leg lengthsbetween each row of surgical fasteners.

Surgical stapling instrument 100 further includes a circular anvilassembly 108 having an anvil head 109 and an anvil shaft 110 extendingfrom a proximal end thereof and adapted to engage a shaft 111 extendingdistally from staple cartridge 118. Anvil head 109 includes an annularanvil member 112 disposed at a proximal end thereof, wherein anvilmember 112 includes at least one, row of fastener forming depressions114 formed circumferentially thereabout. In one embodiment, surgicalstapling instrument 100 includes three laterally spaced rows of fastenerforming depressions 114 formed circumferentially thereabout. Eachfastener forming depression 114 is in registration with a correspondingretention slot 123.

While anvil member 112 is shown in FIG. 2 as having a substantiallyplanar tissue contacting surface, it is envisioned and within the scopeof the present disclosure for surgical stapling instrument 100 to have anumber of alternate configurations. For example, as seen in FIG. 3A,anvil member 112 can have a tissue contacting surface 112 a which isshaped (i.e. stepped) to complement stepped tissue contacting surface121 of staple cartridge 118 or, as seen in FIG. 3B, anvil member 112 canhave a tissue contacting surface 112 b which is stepped while tissuecontacting surface 121 of staple cartridge 118 is substantially planar.In addition, for example, as seen in FIG. 3C, anvil member 112 can haveone row of staple pockets 114 b that extends a greater distance thanstaple pockets 114 a or 114 c into anvil member 112 for accommodatingsurgical fasteners having a longer leg length or, as seen in FIG. 3D,anvil member 112 can have a tissue contacting surface 112 d which isstepped to mirror tissue contacting surface 121 of staple cartridge 118(i.e. the depths of individual tissue contacting surfaces of tissuecontacting surface 112 d of anvil member 112 are substantially equal tothe depths of the individual tissue contacting surfaces 121 a-121 c ofstaple cartridge 118).

The sizes of surgical fasteners 125 a-125 c are selected and intendedfor use in gastric firings typically required in bariatric procedures.However, it is envisioned and within the scope of the present disclosurethat the sizes of surgical fasteners 125 a-125 c selected can be chosenfor performance in different types of tissue, such as, for example, thecolon, bowels, lungs, the bronchus, pulmonary vessels, the liver, andthe like.

In operation, surgical stapling instrument 100 is positioned within atubular organ in the body of the patient and the ends of the organ to bejoined are positioned in a gap between staple cartridge 118 and anvilassembly 108. As is conventional, the ends of the organ may be securedaround anvil shaft 110 by a purse string suture prior to approximationof anvil assembly 108 to staple cartridge 118. Surgical staplinginstrument 100 is then approximated and fired. An example of a surgicalstapling apparatus and methods for its use are disclosed in U.S. Pat.No. 5,915,616, currently assigned to Tyco Healthcare Group LP, theentire contents of which is incorporated herein by reference.

Turning now to FIGS. 4 and 7, a surgical stapling instrument, of thegastro-intestinal anastomosis type for performing surgical anastomoticstapling, in accordance with another embodiment of the disclosure, isgenerally designated as 200. Surgical stapling instrument 200 includes afirst handle 202 having a jaw 230 defining a staple cartridge receivingsection extending from a distal end thereof, a staple cartridge 204receivable in jaw 203, a second handle 206 having a jaw 205 defining ananvil member receiving section extending from a distal end thereof, andan anvil member 208 operatively associated with jaw 205. First andsecond handles 202, 206 are configured such that staple cartridge 204 issubstantially aligned with anvil member 208.

As seen in FIG. 7, staple cartridge 204 includes a stepped tissuecontacting surface 121 including an outer tissue contacting surface 121a, an intermediate tissue contacting surface 121 b, and an inner tissuecontacting surface 121 c, each of which has a different height from oneanother as measured from a bottom surface 231 of staple cartridge 204.Tissue contacting surfaces 121 a-121 c are planar structures that aresubstantially parallel to one another, but are not co-planar with oneanother. For example, tissue contacting surfaces 121 a-121 c, as shownin FIG. 7, can decrease in height in a direction orthogonally outwardfrom knife track 222. In embodiments that do not include knife track222, tissue contacting surfaces 121 a-c decrease in height in adirection orthogonally outward from a centerline of staple cartridge204.

Each tissue contacting surface 121 a-121 c includes a respective linearrow 119 a-119 c of retention slots 123 formed therein. Each retentionslot 123 of linear rows 119 a-119 c is configured and dimensioned toretain a surgical fastener 125 therein. Each linear row 119 a-119 c ofslots 123 includes a respective surgical fastener 125 a-125 c having itsown characteristic features.

As seen in FIG. 7, legs 25 a of surgical fasteners 125 a have a firstleg length of about 4.1 mm, legs 25 b of surgical fasteners 125 b have asecond leg length of about 3.5 mm, and legs 25 c of surgical fasteners125 c have a third leg length of about 2.3 mm. In particular, surgicalfasteners 125 a-125 c increase in height in an orthogonally outwarddirection relative towards optional knife track 222. Knife track 222 isdisposed along a centerline of staple cartridge 204, 310, or 412 and isadapted for slidably receiving an optional knife (not shown). Havingtissue contacting surface 121 step progressively downward atintermediate tissue contacting surface 121 b and then again at outertissue contacting surface 121 a results in the formation of surgicalfasteners 125 b and 125 c, respectively. It is envisioned and within thescope of the present disclosure that any number of arrangements arepossible.

In operation, surgical stapling instrument 200 is fired similarly to andin accordance with other known surgical stapling instruments. An exampleof a surgical stapling apparatus and methods for its use are isdisclosed in U.S. Pat. No. 6,202,914, currently assigned to TycoHealthcare Group LP, the entire contents of which is incorporated hereinby reference.

Referring additionally to FIG. 16, following the firing of surgicalstapling instrument 200, the resulting tissue interface is seen incross-section. Accordingly, surgical fasteners 125 a and 125 b (i.e. thetwo rows of surgical fasteners furthest from knife cut line “C”) serveto hold tissues “A” and “B” to one another while surgical fasteners 125c (i.e. the row of surgical fasteners closest to knife cut line “C”)serve to provide the hemostasis.

While surgical stapling instrument 200 is a linear-type surgicalstapler, it is envisioned and within the scope of the presentdisclosure, that surgical stapling instrument 200 can include a tissuecontacting surface having a cross-sectional profile for at least one ofthe anvil member and the staple cartridge which is substantially similarto the tissue contacting surfaces of the anvil member and the staplecartridge of surgical stapling instrument 100, as shown in FIGS. 3A-3D.

Turning now to FIGS. 5 and 7, a surgical stapling instrument, of thelaparoscopic type for performing surgical anastomotic stapling, inaccordance with another embodiment of the disclosure, is generallydesignated as 300. Surgical stapling instrument 300 includes a handle302, an operative tool 306, and an elongated shaft 304 forinterconnecting operative tool 306 to handle 302. In general, operativetool 306 is designed to clamp over and then to staple and divide tissueheld therein. Accordingly, as seen in FIG. 5, operative tool 306 is apair of opposed jaws including an anvil member 308 and a staplecartridge 310 pivotally coupled to one another.

Staple cartridge 310 of surgical stapling instrument 300 includes astepped tissue contacting surface 121 similar to tissue contactingsurface 121 of staple cartridge 204 of surgical stapling instrument 200.Accordingly, reference is made to FIG. 7 and the above detaileddiscussion of tissue contacting surface 121 of staple cartridge 204 foran illustration and a discussion of tissue contacting surface 121 ofstaple cartridge 310 of surgical stapling instrument 300.

In operation, surgical stapling instrument 300 is fired similarly to andin accordance with other known surgical stapling instruments. For adetailed discussion of the approximation and firing of surgical staplinginstrument 300, reference is made to commonly assigned U.S. Pat. No.5,865,361, currently assigned to Tyco Healthcare Group LP, the entirecontents of which is incorporated herein by reference.

Following the firing of surgical stapling instrument 300 the resultingtissue interface, as seen in cross-section, is substantially similar tothe resulting tissue interface, as seen in cross-section, following thefiring of surgical stapling instruments 100 and 200. Accordingly, asseen in FIG. 16, surgical fasteners 125 a and 125 b (i.e. the two rowsof surgical fasteners furthest from knife cut line “C”) serve to holdtissues “A” and “B” to one another while surgical fasteners 125 c (i.e.the row of surgical fasteners closest to knife cut line “C”) serve toprovide the hemostasis.

While surgical stapling instrument 300 is a linear-type surgical stapleras compared to surgical stapling instrument 100, it is envisioned andwithin the scope of the present disclosure, that surgical staplinginstrument 300 can include a tissue contacting surface having across-sectional profile for at least one of the anvil and the staplecartridge which is substantially similar to the tissue contactingsurfaces of the anvil and the staple cartridge of surgical staplinginstrument 100, as shown in FIGS. 3A-3D.

Turning now to FIGS. 6, 6A, 7, and 7A, a surgical stapling instrument,of the transverse anastomosis type for performing surgical anastomoticstapling, in accordance with yet another embodiment of the disclosure,is generally designated as 400. Surgical stapling instrument 400includes a handle 402, a barrel 404 extending from handle 402, and anarm 406 extending from the distal end of barrel 404. Surgical staplinginstrument 400 further includes an anvil member 408 orthogonally affixedto a distal end of arm 406 and a staple cartridge receiver 410operatively coupled to the distal end of barrel 404 for holding adisposable staple cartridge 412 thereon. Anvil member 408 is illustratedin further detail in FIG. 6A and includes a tissue contacting surface420 wherein tissue contacting surface 420 has a plurality of pockets 425that substantially align with retention slots 123 (FIG. 7). Cooperativealignment between pockets 425 and retention slots 123 form completedsurgical fasteners 125 upon actuation of the actuation mechanism insurgical stapling instrument 400.

Staple cartridge 412 of surgical stapling instrument 400 includes astepped tissue contacting surface 121 similar to tissue contactingsurface 121 of staple cartridge 204 of surgical stapling instrument 200.Accordingly, reference is made to FIG. 7 and the above detaileddiscussion of tissue contacting surface 121 of staple cartridge 204 foran illustration and a discussion of tissue contacting surface 121 ofstaple cartridge 412 of surgical stapling instrument 400. Further still,staple cartridge 412 may include knife track 222 for slidably receivinga knife (not shown) therein.

In a further embodiment of the present disclosure, staple cartridge 412′is illustrated in FIG. 7A and discussed in detail hereinafter. Staplecartridge 412′ is similar to staple cartridge 412, but only includesthree rows 119 a-c of retention slots 123 disposed between outer wallsof staple cartridge 412′. As in the previously discussed embodiment,each row 119 a-c includes a plurality of surgical fasteners whereinsurgical fasteners in row 119 a have a different leg length fromsurgical fasteners disposed in row 119 b, while surgical fastenersdisposed in row 119 c have a leg length that is different from at leastone of rows 119 a or 119 b. This embodiment of the staple cartridge doesnot include a knife track. The arrangement and interrelationship oftissue contacting surfaces 125 a-c is similar to that previouslydisclosed with reference to FIG. 7.

In operation, surgical stapling instrument 400 is fired similarly to andin accordance with other known surgical stapling instruments. For adetailed discussion of the approximation and firing of surgical staplinginstrument 400, reference is made to commonly assigned U.S. Pat. No.5,964,394, currently assigned to Tyco Healthcare Group LP, the entirecontents of which is incorporated herein by reference.

Following the firing of surgical stapling instrument 400 the resultingtissue interface, as seen in cross-section, is substantially similar tothe resulting tissue interface, as seen in cross-section, following thefiring of surgical stapling instruments 100-300. Accordingly, as seen inFIG. 16, surgical fasteners 125 a and 125 b (i.e. the two rows ofsurgical fasteners furthest from knife cut line “C”) serve to holdtissues “A” and to one another while surgical fasteners 125 c (i.e. therow of surgical fasteners closest to knife cut line “C”) serve toprovide the hemostasis.

While surgical stapling instrument 400 is a linear-type surgical stapleras compared to surgical stapling instrument 100, it is envisioned andwithin the scope of the present disclosure, that surgical staplinginstrument 400 can include a tissue contacting surface having across-sectional profile for at least one of the anvil and the staplecartridge which is substantially similar to the tissue contactingsurfaces of the anvil and the staple cartridge of surgical staplinginstrument 100, as shown in FIGS. 3A-3D.

While each of the surgical stapling instruments described above andshown herein are configured and adapted to fire surgical fasteners 125,it is envisioned and within the scope of the present disclosure, thattissue contacting surfaces of surgical instruments used in connectionwith applying two-part fasteners can also have stepped configurations asshown and described herein. A typical two-part surgical fastenerapplying instrument is shown and described in commonly assigned U.S.Pat. No. 5,573,169, currently assigned to Tyco Healthcare Group LP, theentire contents of which is incorporated herein by reference.

In one further embodiment of the present disclosure, as illustrated inFIGS. 8-10, surgical stapling apparatus 300 includes an operative tool506 disposed at one end of elongated shaft 304. Operative tool 506includes anvil member 308 and a staple cartridge 510. Staple cartridge510 may be included in a disposable surgical stapling apparatus or in areusable surgical stapling apparatus. In particular, staple cartridge510 includes a tissue contacting surface 520 having a plurality ofretention slots 523 disposed therein and arranged in rows that aresubstantially aligned with a longitudinal axis of staple cartridge 510.As seen in FIG. 8, each row of retention slots 523 is longitudinallyoffset from an adjacent row of retention slots. In particular, anoptional knife channel 530 is disposed along the longitudinal axis ofstaple cartridge 510 that is adapted for slidably receiving a knife (notshown).

Referring now to FIG. 9, operative tool 506 is shown in cross-sectionand illustrates the several components included in staple cartridge 510.Anvil member 308 includes a substantially planar tissue contactingsurface 320 that is substantially parallel to a bottom surface 512 orparallel to a plane defined by the backspans of surgical fasteners 125a, 125 b, or 125 c. Staple cartridge 510 includes outer walls 514 havinga first height and inner walls 516 having a second height wherein thesecond height is greater than the first height. Tissue contactingsurface 520 is attached to inner walls 516 and to outer walls 514 anddefines an angle with respect to a plane that is orthogonal to innerwalls 516. Tissue contacting surface 520 defines a generally curved pathbetween outer walls 514 (i.e. generally convex or elliptical as viewedin cross-section). Additionally, a plurality of surgical fasteners 125a-c are disposed in staple cartridge 510 wherein each row of retentionpockets 523 includes a number of substantially identical surgicalfasteners (i.e. 125 a, 125 b, or 125 c). Similar to previousembodiments, legs 25 a-c of surgical fasteners 125 a-c have differentlengths. In this embodiment, surgical fasteners 25 a have a leg lengthof about 3.8 mm, surgical fasteners 25 b have a leg length of about 3.5mm, and surgical fasteners 25 c have a leg length of about 2.5 mm. Asseen in FIG. 9, surgical fasteners 125 a-c are disposed in staplecartridge 510 such that surgical fasteners 125 c are proximate to outerwalls 514, surgical fasteners 125 a are disposed proximate to innerwalls 516, and surgical fasteners 125 b are disposed therebetween. Incooperation with the surgical fasteners of varying height, staplecartridge 510 includes fastener ejection members 540 that include staplepushers 542, 544, and 546 of differing heights. Staple pusher 542 hasthe greatest height dimension, staple pusher 546 has the least heightdimension, and staple pusher 544 has a height dimension therebetween. Inthis embodiment, surgical fasteners 125 a-c are arranged to cooperatewith staple pushers 546, 544, and 542 respectively. Fastener ejectionmember 540 is adapted for substantially vertical movement when itcooperatively engages with an actuation mechanism (not shown). Anexample of a suitable actuation mechanism is disclosed in U.S. Pat. No.5,865,361 as discussed with reference to previously disclosed surgicalstapling instrument 300.

Alternatively, as shown in FIG. 10, surgical fasteners 125 a-c aredisposed in staple cartridge 510′ such that surgical fasteners 125 a areproximate to outer walls 514, surgical fasteners 125 c are disposedproximate to inner walls 516, and surgical fasteners 125 b are disposedtherebetween. Contrary to the previous embodiment, surgical fasteners125 a-c are arranged to cooperate with staple pushers 542, 544, and 546respectively. After a number of layers of body tissue are positionedbetween tissue contacting surfaces 320 and 520, the actuation mechanismis actuated for sequentially ejecting surgical fasteners 125 a-c throughretention slots 523 whereby interaction between surgical fasteners 125a-c and anvil member 308 forms completed surgical fasteners for joiningthe layers of body tissue.

When tissue contacting surface 320 of anvil member 308 is repositionedproximate to tissue contacting surface 520 of staple cartridge 510′, theamount of pressure applied to the layers of tissue disposed therebetweenvaries along a plane that is transverse to the longitudinal axis ofstaple cartridge 510′. Since the distance between tissue contactingsurfaces 320 and 520 is at a minimum in the region nearest inner walls516 (i.e. the centerline of staple cartridge 510′), a maximum pressureis applied to the layers of tissue disposed in this region. Conversely,the distance between tissue contacting surfaces 320 and 520 is at amaximum in the region near outer walls 514, a minimum pressure isapplied to the layers disposed in this region. In addition, the proximalrelationship between anvil member 308 and staple cartridge 510′ definesa plurality of gaps therebetween. A first gap is defined between tissuecontacting surfaces 320 and 520 (i.e. along the centerline of staplecartridge 510′), while a second gap is defined between tissue contactingsurfaces 320 and 520 along outer walls 514. As seen in FIG. 10, thefirst gap is not equal to the second gap. Further still, a number ofother gaps may be defined between tissue contacting surfaces 320 and 520at other points of reference existing between the centerline and outerwalls 514 in staple cartridge 510′. Since tissue contacting surface 520slopes toward outer walls 514 to define a substantially uniform angle,the pressure applied to the layers of tissue disposed between tissuecontacting surfaces 320 and 520 uniformly decreases from inner wall 516to outer wall 514.

By angling tissue contacting surface 520 downwards from the centerlineof staple cartridge 510′, reduced compressive forces are applied to thelayers of tissue disposed between tissue contacting surfaces 320 and 520thereby minimizing trauma to the layers of tissue disposed therebetween.Therefore, layers of tissue disposed between tissue contacting surfaces320 and 520 will have a minimum thickness nearest knife channel 530(i.e. nearest the centerline of staple cartridge 510′) and a maximumthickness nearest outer walls 514. In addition, anvil member 308 andstaple cartridge 510′ are dimensioned and arranged such that compressiveforces applied to the layers of tissue are minimal thereby furtherreducing trauma to the layers of tissue. This configuration defines agap between tissue contacting surfaces 320 and 520 that is a maximumalong knife channel 530 (i.e. the centerline of staple cartridge 510 or510′) and a minimum along outer walls of staple cartridge 510 (FIG. 9)or 510′ (FIG. 10).

Further still, this configuration is applicable to similar staplecartridges and anvil members as will be discussed in detail hereinafterwith respect to FIGS. 11-15. When anvil member 308 is repositioned intoproximity with staple cartridge 510′ (i.e. in a pre-fire position) toretain layers of body tissue therebetween, the layers of tissue arecompressed. The maximum compression occurs along the centerline (i.e.first or minimum gap) and urges fluid stored in the layers of tissuetowards the outer edges of the tissue (i.e. away from the centerline ofstaple cartridge 510′). By reducing the amount of fluid retained in thelayers of tissue proximal to the centerline, the overall thickness ofthe tissue layers decreases. The decrease in overall tissue thickness issuch that a staple having a shorter leg length (i.e. surgical fastener125 c) is capable of fastening both layers of tissue while minimizingtrauma to the fastened layers of tissue. The gap increases towards theouter walls of staple cartridge 510′ (i.e. the amount of compressiondecreases) and surgical fasteners having a longer leg length (i.e.surgical fasteners 125 a and 125 b) are capable of fastening both layersof tissue.

Leg lengths of surgical fasteners 125 c, 125 b, and 125 a increase in adirection moving from inner walls 516 towards outer walls 514. Byproviding surgical fasteners having increasing leg lengths along a planethat is orthogonal to inner walls 516, the completed (i.e. formed)surgical fasteners join increasing thicknesses of tissue without undulytraumatizing the joined layers of tissue.

In a further embodiment, as illustrated in FIG. 11, operative tool 506″includes staple cartridge 510′ and anvil member 308′. Staple cartridge510′ was previously discussed in detail hereinabove with reference toFIG. 10. Tissue contacting surface 520 may define a more uniform angle(FIG. 11) than in the embodiments of FIGS. 9 and 10 wherein the angle orpitch of tissue contacting surface is substantially constant betweeninner walls 516 and outer walls 514. Anvil member 308′ includes tissuecontacting surface 320′ having tapered surfaces 322′ and 324′. Surfaces322′ and 324′ are connected to outer walls of anvil member 308′ whileextending inwards (i.e. towards the centerline of staple cartridge 510′)and downwards (i.e. towards tissue contacting surface 520) therebydefining an angle. It is envisioned that the angle defined by taperedsurfaces 322′ and 324′ will be substantially similar to the angledefined by tissue contacting surface 520, but in an opposed directionforming a generally V-shaped configuration. Thus, compressive forcesapplied to the layers of tissue will be further reduced thereby furtherreducing the trauma to layers of tissue disposed between tissuecontacting surfaces 520 and 320′. As in the embodiment of FIG. 10, themaximum pressure applied to the layers of tissue will exist in theregion near knife channel 530 while pressures applied to the layers oftissue will decrease uniformly towards outer walls 514. Formation andlocation of surgical fasteners 125 a-c is substantially similar to thatof the embodiment of FIG. 10 along with the attendant advantages.

Referring now to FIG. 12, a further embodiment of the present disclosureis shown as part of operative tool 606. Operative tool 606 includes astaple cartridge 610 and anvil member 308. In this embodiment, tissuecontacting surface 620 includes surfaces 622 and 624. Surface 622 isbisected along its longitudinal axis by knife channel 630 andsubstantially parallel to a bottom surface 612 or parallel to a planedefined by the backspans of surgical fasteners 125 a, 125 b, or 125 c.In addition, surface 622 has a width dimension sufficient to accommodateat least one row of retention slots 623 on each side of knife channel630. Surface 624 connects outer edges of surface 622 to outer walls 614defining an angle on either side of knife channel 630 with respect to aplane that is substantially orthogonal to inner walls 616 (i.e.substantially parallel to surface 622) and has a width dimensionsufficient to accommodate at least one row of retention slots on eachside of knife channel 630. Staple cartridge 610 includes a plurality ofsurgical fasteners 125 a-c and fastener ejection members 540 that werepreviously discussed in detail with respect to FIGS. 9 and 10. Inparticular, staple cartridge 610 includes the arrangement of surgicalfasteners 125 a-c and fastener ejection members 540 as described withrespect to staple cartridge 510′ (FIGS. 10 and 11).

Similarly to operative tool 506, tissue contacting surface 320 isrepositioned proximate to tissue contacting surface 620 of staplecartridge 610. In this arrangement, the amount of pressure applied tothe layers of tissue disposed therebetween varies along a plane that istransverse to the longitudinal axis of staple cartridge 610.Specifically, the distance between tissue contacting surface 320 andsurface 622 is a minimum, a maximum pressure is applied to the layers oftissue disposed in this region. Conversely, the distance between tissuecontacting surface 320 and surfaces 624 is at a maximum in the regionnear outer walls 614, a minimum pressure is applied to the layersdisposed in this region. Since surface 624 slopes toward outer walls 614to define a substantially uniform angle, the pressure applied to thelayers of tissue disposed between tissue contacting surface 320 andsurfaces 624 uniformly decreases from an outer edge of surface 622towards outer wall 614.

By angling surface 624 downwards from the edge of surface 622, reducedcompressive forces are applied to the layers of tissue disposed betweentissue contacting surface 320 and surfaces 624 thereby minimizing traumato the layers of tissue disposed therebetween. Layers of tissue disposedbetween tissue contacting surfaces 320 and 620 will have a minimumthickness nearest knife channel 630 and a maximum thickness nearestouter walls 614. In addition, anvil member 308 and staple cartridge 610are dimensioned and arranged such that compressive forces applied to thelayers of tissue are minimal thereby further reducing trauma to thelayers of tissue.

Leg lengths of surgical fasteners 125 c, 125 b, and 125 a increase in adirection moving from inner walls 616 towards outer walls 614. Byproviding surgical fasteners having increasing leg lengths along a planethat is orthogonal to inner walls 616, the completed (i.e. formed)surgical fasteners join increasing thicknesses of tissue without undulytraumatizing the joined layers of tissue.

In a further embodiment, operative tool 606′ is illustrated in FIG. 13.Operative tool 606′ includes staple cartridge 610, that was described indetail hereinabove with respect to FIG. 12, and anvil member 608. Anvilmember 608 includes a tissue contacting surface 620 formed from surfaces632 and 636. Surface 636 is substantially parallel to surface 622 andhas a width dimension that is substantially similar to the widthdimension of surface 622. Surfaces 632 are tapered and connected toouter walls of anvil member 608 and extend inwards (i.e. towards thecenterline of staple cartridge 610) and downwards (i.e. towards tissuecontacting surface 620) thereby defining an angle. It is envisioned thatthe angle defined by tapered surfaces 632 will be substantially similarto the angle defined by surfaces 624, but in an opposed direction. Thus,compressive forces applied to the layers of tissue will be furtherreduced thereby further reducing the trauma to layers of tissue disposedbetween surfaces 624 and 632. As in the embodiment of FIG. 10, themaximum pressure applied to the layers of tissue will exist in theregion along surface 622 while pressures applied to the layers of tissuewill decrease uniformly along surfaces 624 towards outer walls 614.Formation and location of surgical fasteners 125 a-c is substantiallysimilar to that of the embodiment of FIG. 12 along with the attendantadvantages.

In yet another embodiment, operative tool 706 is illustrated in FIG. 14.Staple cartridge 710 is similar to staple cartridge 610. The differencesbetween staple cartridges 610 and 710 will be discussed hereinafter. Asin staple cartridge 610 (FIG. 12), staple cartridge 710 includes tissuecontacting surface 720 formed from surfaces 722 and 724. Surface 722differs from surface 622 in that it has a width dimension sufficient toaccommodate at least two rows of surgical fasteners. As in staplecartridge 610, surfaces 724 are attached to outer edges of surface 722and outer walls 714 to define angles. The interaction between staplecartridge 710 and anvil member 308 for capturing tissue and formingsurgical fasteners is substantially similar to the interaction betweenstaple cartridge 610 and anvil member 308 and, for the sake of brevity,will not be repeated herein.

In a further embodiment, operative tool 706′ is shown in FIG. 15 andincludes staple cartridge 710, as described with respect to FIG. 14, andanvil member 708. Anvil member 708 includes a tissue contacting surface720 formed from surfaces 732 and 736. Surface 736 is substantiallyparallel to surface 722 and has a width dimension that is substantiallysimilar to the width dimension of surface 722. Surfaces 732 are taperedand connected to outer walls of anvil member 708 and extend inwards(i.e. towards the centerline of staple cartridge 710) and downwards(i.e. towards tissue contacting surface 720) thereby defining an angle.It is envisioned that the angle defined by tapered surfaces 732 will besubstantially similar to the angle defined by surfaces 724, but in anopposed direction. Thus, compressive forces applied to the layers oftissue will be further reduced thereby further reducing the trauma tolayers of tissue disposed between surfaces 724 and 732. As in theembodiment of FIG. 14, the maximum pressure applied to the layers oftissue will exist in the region along surface 722 while pressuresapplied to the layers of tissue will decrease uniformly along surfaces724 towards outer walls 714. Formation and location of surgicalfasteners 125 a-c is substantially similar to that of the embodiment ofFIG. 14 along with the attendant advantages.

In FIG. 15, an alternate embodiment of operative tool 706′ isillustrated. Operative tool 706′ includes staple cartridge 710, asdiscussed in detail hereinabove, and anvil member 708. Anvil member 708includes a tissue contacting surface 720 formed from surfaces 732 and736. Surface 736 is substantially parallel to surface 722 and has awidth dimension that is substantially similar to a width dimension ofsurface 722. Surfaces 732 are tapered and connected to outer walls ofanvil member 708 and extend inwards (i.e. towards centerline of staplecartridge 710) and downwards (i.e. towards tissue contacting surface720) thereby defining an angle. It is envisioned that the angle definedby tapered surfaces 732 will be substantially similar to the angledefined by surfaces 724, but in an opposed direction. Thus, compressiveforces applied to the layers of tissue will be further reduced, therebyfurther reducing the trauma to the layers of tissue disposed betweensurfaces 724 and 732. As in the embodiment of FIG. 14, the maximumpressure applied to the layers of tissue will exist in the region alongsurface 722 while pressures applied to the layers of tissue willdecrease uniformly along surfaces 724 towards outer walls 714. Formationand location of surgical fasteners 125 a-c is substantially similar tothat of the embodiment of FIG. 14 along with the attendant advantages.

Turning now to FIG. 16, a cross-section of the resulting tissueinterface, following the firing of staple cartridge 510′, is shown. Asseen in FIG. 16, the tissue interface has a substantially taperedprofile. In particular, surgical fasteners 125 a and 125 b (i.e. the tworows of surgical fasteners furthest from knife cut line “C”) serve tohold tissues “A” and “B” to one another while surgical fasteners 125 c(i.e. the row of surgical fasteners closest to knife cut line “C”) serveto provide the hemostasis. This resulting cross-section is alsoapplicable to the firing of staple cartridges 610 and 710. When staplecartridge 510 is fired, surgical fasteners 125 b and 125 c (i.e. the tworows of surgical fasteners furthest from knife cut line “C”) serve tohold tissues “A” and “B” to one another while surgical fasteners 125 a(i.e. the row of surgical fasteners closest to knife cut line “C”) serveto provide the hemostasis.

In a further embodiment of the present disclosure, as shown in FIGS. 8and 10, operative tool 506′ includes a wound closure assembly 50. Woundclosure assembly 50 includes at least one storage device or reservoir 52and at least one supply line 54. Supply line 54 fluidly couplesreservoir 52 to staple cartridge 510′ for delivering an amount of awound closure material “W”. In particular, supply line 54 delivers woundclosure material “W” into knife channel 530 such that when surgicalfasteners 125 a-c are formed, wound closure material “W” migrates alongthe layers of tissue adjacent to tissue contacting surface 520 (i.e. thetarget site). By providing wound closure material “W” in combinationwith surgical fasteners 125 a-c, the bond formed between the layers oftissue has improved strength.

Compression of reservoir 52 causes wound closure material “W” containedtherein to be urged through supply line 54 and dispensed via knifechannel 530. Preferably, wound closure material “W” is dispensed duringthe staple firing procedure so that wound closure material “W” isdispensed along the length of the staple line and/or a knife cut line.Although wound closure assembly is discussed and illustrated withrespect to FIG. 10, it is contemplated that wound closure assembly 50 isadaptable for use with other disclosed embodiments of staple cartridge510′ (i.e. 510, 610, or 710). It is further contemplated that anadditional reservoir may be included for wound closure materials formedby combining two substances or that reservoir 52 may include a pluralityof internal chambers (shown in phantom) for storing quantities ofsubstances to be combined to form wound closure material “W”. Furtherstill, wound closure assembly 50 may be included in surgical staplingapparatus 100 (FIG. 1) wherein at least one opening 56 is disposed in awall of anvil shaft 110 for dispensing wound closure material “W”.

It is envisioned that wound closure material “W” can include one or acombination of adhesives, hemostats, sealants. Surgical biocompatiblewound closure materials which can be employed in or applied the surgicalinstruments, especially surgical staplers, include adhesives whosefunction is to attach or hold organs, tissues or structures, sealants toprevent fluid leakage, and hemostats to halt or prevent bleeding.Examples of adhesives which can be employed include protein derived,aldehyde-based adhesive materials, for example, the commerciallyavailable albumin/glutaraldehyde materials sold under the tradedesignation BioGlue™ by Cryolife, Inc., and cyanoacrylate-basedmaterials sold under the trade designations Indermil™ and Derma Bond™ byTyco Healthcare Group, LP and Ethicon Endosurgery, Inc., respectively.Examples of sealants, which can be employed, include fibrin sealants andcollagen-based and synthetic polymer-based tissue sealants. Examples ofcommercially available sealants are synthetic polyethylene glycol-based,hydrogel materials sold under the trade designation CoSeal™ by CohesionTechnologies and Baxter International, Inc. Examples of hemostatmaterials, which can be employed, include fibrin-based, collagen-based,oxidized regenerated cellulose-based and gelatin-based topicalhemostats. Examples of commercially available hemostat materials arefibrinogen-thrombin combination materials under sold the tradedesignations CoStasis™ by Tyco Healthcare Group, LP, and Tisseel™ soldby Baxter International, Inc. Hemostats herein include astringents,e.g., aluminum sulfate, and coagulants.

It is to be understood that the dispensing of wound closure material “W”can be as a fluid spray of any suitable volume, including a mist,applied temporarily, continuously, or continually. Particulate material,e.g. a fine powder is contemplated to be a fluid within the scope ofthis disclosure.

It is provided that a number of different wound closure materials “W”can be dispensed by wound closure assembly 50 or a combination of thenumber of different wound closure materials “W”. The wound closurematerial dispensed by wound closure assembly 50 can, for example, be anastringent, such as a sulfate of aluminum, which causes small bloodvessels to close and helps the blood to coagulate. It is provided thatwound closure material “W” can be an astringent provided in the materialcommercially available under the trade designation No Nix StypticPencils from Requa™, Inc.

In addition, while each of the surgical stapling instruments describedabove and shown herein include tissue contacting surfaces having astepped profile, it is envisioned that any of the surgical staplinginstruments disclosed herein can have tissue contacting surfaces havingany one of a number of profiles including and not limited to angles,conical, tapered, arcuate and the like, as disclosed in commonlyassigned U.S. patent application Ser. No. 10/411,686, filed on May 11,2003, entitled “Surgical Stapling Apparatus Including an Anvil andCartridge Each Having Cooperating Mating Surfaces,” currently assignedto Tyco Healthcare Group LP, the entire contents of which isincorporated herein by reference.

It will be understood that various modifications may be made to theembodiments of the presently disclosed surgical stapling instruments.Therefore, the above description should not be construed as limiting,but merely as exemplifications of embodiments. Those skilled in the artwill envision other modifications within the scope and spirit of thepresent disclosure.

1. A surgical stapling apparatus comprising: a staple cartridge havingfirst and second surfaces, the first and second surfaces each include aplurality of retention slots and define a planar axis, each retentionslot being dimensioned to receive a surgical fastener, the first surfacebeing adjacent to the second surface wherein the first planar axis doesnot intersect the second planar axis; an anvil member cooperative withthe staple cartridge such that when the anvil member is proximate to thestaple cartridge a plurality of gaps are defined therebetween, wherein afirst gap between the first surface and the anvil member is not equal toa second gap between the second surface and the anvil member.
 2. Theapparatus of claim 1, wherein the first gap is less than the second gapand the second gap is more proximate an outer surface of said staplecartridge than the first gap.
 3. The apparatus of claim 1, furtherincluding at least one fastener ejection member, wherein actuation of anactuation mechanism causes the at least one fastener ejection member totranslate through the staple cartridge such that the surgical fastenersare ejected from their respective retention slots.
 4. The apparatus ofclaim 1, wherein surgical fasteners of the first surface have a firstleg length and surgical fasteners in the second surface have a secondleg length and the first leg length is different from the second leglength.
 5. The apparatus of claim 1, wherein the anvil member has asubstantially planar tissue contacting surface.
 6. The apparatus ofclaim 1, wherein the anvil member has at least two surfaces that aresubstantially parallel to each other.
 7. The apparatus of claim 6,wherein the at least two surfaces of the anvil member define a steppedarrangement that substantially corresponds to a stepped arrangementdefined by the at least two surfaces of the staple cartridge.
 8. Theapparatus of claim 6, wherein the at least two surfaces of the anvilmember define a stepped arrangement that substantially diverges from astepped arrangement defined by the at least two surfaces of the staplecartridge.
 9. The apparatus of claim 6, wherein the at least twosurfaces of the staple cartridge and the corresponding surfaces of theanvil member are annular.
 10. The apparatus of claim 1, furthercomprising a passage fluidly coupled to the staple cartridge fordelivering a quantity of a wound closure material to at least one of thesurfaces of the staple cartridge.